1. Field of the Invention
This invention relates to tools for removing engine radiator caps. In particular, the invention relates to a tool, that without modification, fits all different styles of engine radiator caps, including automobile, truck, and stationary engines, among others.
2. Description of Related Art Including Information Disclosed under 37 C.F.R. Sections 1.97-1.99
The prior art reveals numerous radiator cap removal tools. Many such tools are deficient because they are not suitable for use with all styles of radiator caps. In addition, use of such tools may place the user's hand so close to the radiator cap that hot fluid is likely to spray the hand when removing the radiator cap from a hot radiator. Many such tools cannot be used on radiator caps that are not mounted on the top of the radiator. If they are not kept in the car, truck, or near a stationary engine at all times, they may not be available when the radiator overheats or it is desired to remove the radiator cap for other purposes, such as routine filling or other service work.
Some of these tools enable the user to loosen the radiator cap, but do not allow the same tool to be used in actually removing the radiator cap from the radiator filler neck. A separate tool, such as a pair of pliers or a rag, which are often unavailable at the moment of need, is needed for actually removing the hot radiator cap.
Furthermore, all such tools are easily misplaced simply because they are used so infrequently that the owner does not keep them with the vehicle, or easily recall where he left them. Finally, many such tools are awkwardly shaped and accordingly, unwieldy in use and wholly unsuitable for permanent installation.
Furthermore, most modern automobile radiators are equipped with a coolant recovery system that collects and condenses vapors escaping from the radiator during operation of the engine. The condensed fluids are returned to the radiator and engine cooling system by ambient air pressure that exceeds the fluid pressure inside the cooling system when the engine cools. When such coolant recovery system is employed, the radiator cap typically is designed to be loosened by turning about one-quarter turn counterclockwise, where it engages a pressure release stop-tooth on an outer flange of the radiator filler neck. When the radiator cap is in this position, vapor pressure will be released from the radiator and cooling system, but the cap cannot be removed from the radiator filler neck, thereby reducing the chance of injury from splashing hot fluid. After the cooling system pressure reaches equilibrium with the ambient air pressure, the radiator cap can be safely removed by depressing it firmly and rotating it approximately another one-half turn counterclockwise, allowing the radiator cap to be lifted free of the filler neck.
Most tools for removing radiator caps, including the human hand, require the user to press down hard on the radiator cap to develop a sufficient grip to overcome the friction between the radiator cap gasket and the lip of the filler neck and to rotate the radiator cap. When the radiator cap is thus depressed, it is easy, and all too common, to rotate the radiator cap past the pressure release stop-tooth. If this happens and the radiator is hot, the cap is likely to be explosively thrown from the radiator as superheated fluids gush out of the radiator filler neck, and injury to the person is very likely. Such injuries can be very serous and may include, for example, the loss of sight. In addition, exposure to antifreeze can dangerously damage a vehicle's finish.
Most modern vehicles have little spare room in the engine compartment, with the engine and ancillary equipment virtually stuffed into the engine compartment. Often, the radiator cap is mounted in a manner or location that is difficult to reach, or if it can be easily reached, it may be difficult to apply enough force to remove the cap because of the curve of the wrist that the mechanic must assume to reach the cap.
Attempts to overcome these problems have led to many prior patents. Many are directed to devices for attempting to prevent burns either from the splashing of hot fluids onto the user or simply from touching hot parts, and are consequently fairly large tools that cannot be left in place on the radiator cap. Examples of this type of tool are found in U.S. Pat. Nos. 5,003,845; 4,914,985; 4,697,480; 3,885,477; 3,837,242; 3,638,515; 3,274,864; 3,186,263; 3,048,067; and 3,014,389. The possibility of not having tools such as these available when needed is quite high, especially for the ordinary motorist.
Therefore, a need exists for a tool for removing radiator caps that can be used without modification for all styles of radiator caps; that will permit convenient removal a radiator cap that is not mounted on the top of the radiator; that is easy to use; that will not become lost; that is always available when needed; that can easily be used for actually removing the radiator cap from the radiator neck, as well as for loosening it; and that is simple and inexpensive to design, manufacture and to install.